1. Field of the Invention:
This invention relates to a solar battery module for converting the energy of sunlight into electrical energy and a method for the production thereof.
2. Description of the Prior Art:
The solar battery module is constructed by having a multiplicity of solar battery elements carried on a supporting base plate. When the sunlight impinges on the individual solar battery elements, the energy of the light which makes no contribution to the photoelectric conversion is accumulated in the form of heat to elevate the temperature of the solar battery elements and lower the efficiency of photoelectric conversion. Thus, various devices have been contrived for the material and construction of the supporting base plate for the purpose of conferring an improved ability to release heat on the supporting base plate.
As solar battery modules possessing supporting constructions which allow relatively satisfactory release of heat, such honeycomb structures as have solar battery elements joined thereto which are disclosed in Japanese Patent Publication No. 62-40,873, Japanese Utility Model Publication No. 4-42,945, and Japanese Patent Publication No. 5-56,672 have been heretofore known.
As means for producing these solar battery modules, a method which comprises setting a plurality of solar battery elements fast on the surface of a honeycomb structure through the medium of an adhesive agent and simultaneously pressing the plurality of solar battery elements thereby causing the adhesive agent to cure under the pressure and join them as disclosed in Japanese Patent Publication No. 62-40,873 and a method which comprises placing a sheet of thermoplastic resin on the surface of a honeycomb structure, setting a plurality of solar battery elements in place thereon, sequentially superposing a sheet of thermoplastic resin and a transparent PVF film in the order mentioned on the solar battery elements, setting the resultant superposed layers in a laminating device, heating them in a vacuum, and pressing them in a vacuum state thereby joining them as disclosed in Japanese Utility Model Publication No. 4-42,945 have been heretofore known to the art.
The former method of production, however, is deficient in operational efficiency of production because it entails a troublesome work of applying the adhesive agent to one after another of the plurality of solar battery elements.
The latter method of production effects the production more efficiently than the former method of production because it joins the plurality of solar battery elements to the surface of the honeycomb structure by the use of the sheet of thermoplastic resin. The latter method of production, however, suffers the ambient air to be locally entrapped between the sheet of thermoplastic resin and the surface of the honeycomb structure and the captive air to be eventually enfolded in the form of bubbles fast in the interface between the sheet of thermoplastic resin and the surface of the honeycomb structure. Since the sheet of thermoplastic resin and the surface of the honeycomb structure are not joined in the portions of the bubbles, the union thereof lacks uniformity. The portions of the sheet of thermoplastic resin corresponding to the bubbles are raised from the rest of the sheet and causes the solar battery element to form a distorted surface.
The plurality of solar battery elements, therefore, cannot be joined to the surface of the honeycomb structure in such a uniform state as allows the surfaces of the individual solar battery elements to form a uniform flat surface which is free from distortion.